Castlehaven, whose date of birth is unknown, was born into an well-known Anglo-Irish Catholic family with a history of military service and loyalty to the English crown. His father eventually took the oaths to William III and his seat in the Lords. In August 1700 Narcissus Luttrell‡ noted that the son had recently returned from ‘travelling beyond sea at his majesty’s charge’.4 Luttrell, Brief Relation, iv. 677. The pension of £300 p.a. granted by William III to his father was reported to be one year and three-quarters in arrears at the king’s death, suggesting that it may have been transferred to his son.5 CTB, xvii. 954.
In March 1705 Castlehaven was listed as one of those Catholics licensed to bear arms in Ireland.6 HMC Ormonde, ii. 475. He married into another important English Catholic family, the Arundells of Wardour, but apparently took no active part in English or Irish politics. However, his name appears on two parliamentary lists: on a printed list of the first Parliament of Great Britain in 1708 he was marked as underage and given the assignation Whig, which was then crossed out; on the division list of 20 Mar. 1710 on Sacheverell he was listed as a Roman Catholic.
In 1716 Castlehaven was mentioned in Jacobite intrigue.7 HMC Stuart, ii. 206. He died in Paris on either 12 or 29 Oct. 1740 and was buried at St Sulpice, Paris. His widow died on 16 June 1743 and was buried at St Pancras, Middlesex. He was succeeded by his son James Tuchet†, 17th Baron Audley and 7th earl of Castlehaven [I].